VANCE: On the one hand, we have to be cautious. Everything that Mr. Parnas, who is someone who is under indictment, everything that he has says to be corroborated. But at the same time it is very consistent with testimony that we have heard from other witnesses. In some cases it seems to fill in blanks. And something that impressed me was when it came to these allegations -- or rather the text messages from Robert Hyde about the surveillance and perhaps threat to Ambassador Yovanovitch, Parnas would not go there. And he said. "No, I knew that he wasn't for real." That I think builds his credibility. If he was making everything up, he would have agreed to that as well. But he put the brakes on.

WILLIAMS: He used a double negative in fact when describing Mr. Hyde. He said, "I've never seen him when he he wasn't drunk." And that was notable. Additionally, to say, "Who am I? Why would these people meet with me?" That's the opposite of a claim of grandiosity that you sometimes get with big-level witnesses.

VANCE: There are these little moments with witnesses that help juries decide whether or not to believe them. And it's an informal moment like that where he sort of puts out his hands and says, "Why else would they meet with me?" And that's very credible.

VANCE: So this was actually not a leak. This was an official, sanctioned process, where Parnas' attorney asked for permission to turn material over, received permission to turn it over. So when the FBI does an image, say, of a cell phone, that's just a big raw piece of data you that get back. Some work has to be done to make it usable. And that is then what we saw Parnas and his attorney work very quickly, as we heard Rachel say, to turn that over so it would be part of the record the House transmitted to the Senate. Once the House transmitted the articles of impeachment, that record was closed. So, there was apparently a rush at the end to include this material in the record that the Senate can consider if it chooses to look at the evidence.

WILLIAMS: And I heard it put tonight that it's further of benefit to Mr. Parnas that he has not had these devices in his possession for weeks, if not months. There's been no ability on his part to go back and correct or delete things.

VANCE: That's right. At least that's technically correct. There's no reason to believe those devices would not have been secured to prevent, say, some alteration using the cloud. That would have been detected. They were probably turned off and images were taken immediately. And it's those images that were taken at the time that they were seized that would be used to generate evidence. So this works in Parnas' favor. The fact he's turning information over while he's still under indictment. And that could conceivably be used against him. Certainly his statements tonight. These are factors that tend to build credibility for him.